security/tomoyo/common.c

   1 /*
   2  * security/tomoyo/common.c
   3  *
   4  * Common functions for TOMOYO.
   5  *
   6  * Copyright (C) 2005-2010  NTT DATA CORPORATION
   7  */
   8
   9 #include <linux/uaccess.h>
  10 #include <linux/slab.h>
  11 #include <linux/security.h>
  12 #include "common.h"
  13
  14 static struct tomoyo_profile tomoyo_default_profile = {
  15         .learning = &tomoyo_default_profile.preference,
  16         .permissive = &tomoyo_default_profile.preference,
  17         .enforcing = &tomoyo_default_profile.preference,
  18         .preference.enforcing_verbose = true,
  19         .preference.learning_max_entry = 2048,
  20         .preference.learning_verbose = false,
  21         .preference.permissive_verbose = true
  22 };
  23
  24 /* Profile version. Currently only 20090903 is defined. */
  25 static unsigned int tomoyo_profile_version;
  26
  27 /* Profile table. Memory is allocated as needed. */
  28 static struct tomoyo_profile *tomoyo_profile_ptr[TOMOYO_MAX_PROFILES];
  29
  30 /* String table for functionality that takes 4 modes. */
  31 static const char *tomoyo_mode_4[4] = {
  32         "disabled", "learning", "permissive", "enforcing"
  33 };
  34
  35 /* String table for /sys/kernel/security/tomoyo/profile */
  36 static const char *tomoyo_mac_keywords[TOMOYO_MAX_MAC_INDEX
  37                                        + TOMOYO_MAX_MAC_CATEGORY_INDEX] = {
  38         [TOMOYO_MAC_FILE_EXECUTE]    = "file::execute",
  39         [TOMOYO_MAC_FILE_OPEN]       = "file::open",
  40         [TOMOYO_MAC_FILE_CREATE]     = "file::create",
  41         [TOMOYO_MAC_FILE_UNLINK]     = "file::unlink",
  42         [TOMOYO_MAC_FILE_MKDIR]      = "file::mkdir",
  43         [TOMOYO_MAC_FILE_RMDIR]      = "file::rmdir",
  44         [TOMOYO_MAC_FILE_MKFIFO]     = "file::mkfifo",
  45         [TOMOYO_MAC_FILE_MKSOCK]     = "file::mksock",
  46         [TOMOYO_MAC_FILE_TRUNCATE]   = "file::truncate",
  47         [TOMOYO_MAC_FILE_SYMLINK]    = "file::symlink",
  48         [TOMOYO_MAC_FILE_REWRITE]    = "file::rewrite",
  49         [TOMOYO_MAC_FILE_MKBLOCK]    = "file::mkblock",
  50         [TOMOYO_MAC_FILE_MKCHAR]     = "file::mkchar",
  51         [TOMOYO_MAC_FILE_LINK]       = "file::link",
  52         [TOMOYO_MAC_FILE_RENAME]     = "file::rename",
  53         [TOMOYO_MAC_FILE_CHMOD]      = "file::chmod",
  54         [TOMOYO_MAC_FILE_CHOWN]      = "file::chown",
  55         [TOMOYO_MAC_FILE_CHGRP]      = "file::chgrp",
  56         [TOMOYO_MAC_FILE_IOCTL]      = "file::ioctl",
  57         [TOMOYO_MAC_FILE_CHROOT]     = "file::chroot",
  58         [TOMOYO_MAC_FILE_MOUNT]      = "file::mount",
  59         [TOMOYO_MAC_FILE_UMOUNT]     = "file::umount",
  60         [TOMOYO_MAC_FILE_PIVOT_ROOT] = "file::pivot_root",
  61         [TOMOYO_MAX_MAC_INDEX + TOMOYO_MAC_CATEGORY_FILE] = "file",
  62 };
  63
  64 /* Permit policy management by non-root user? */
  65 static bool tomoyo_manage_by_non_root;
  66
  67 /* Utility functions. */
  68
  69 /**
  70  * tomoyo_yesno - Return "yes" or "no".
  71  *
  72  * @value: Bool value.
  73  */
  74 static const char *tomoyo_yesno(const unsigned int value)
  75 {
  76         return value ? "yes" : "no";
  77 }
  78
  79 /**
  80  * tomoyo_print_name_union - Print a tomoyo_name_union.
  81  *
  82  * @head: Pointer to "struct tomoyo_io_buffer".
  83  * @ptr:  Pointer to "struct tomoyo_name_union".
  84  *
  85  * Returns true on success, false otherwise.
  86  */
  87 static bool tomoyo_print_name_union(struct tomoyo_io_buffer *head,
  88                                  const struct tomoyo_name_union *ptr)
  89 {
  90         int pos = head->read_avail;
  91         if (pos && head->read_buf[pos - 1] == ' ')
  92                 head->read_avail--;
  93         if (ptr->is_group)
  94                 return tomoyo_io_printf(head, " @%s",
  95                                         ptr->group->group_name->name);
  96         return tomoyo_io_printf(head, " %s", ptr->filename->name);
  97 }
  98
  99 /**
 100  * tomoyo_print_number_union - Print a tomoyo_number_union.
 101  *
 102  * @head:       Pointer to "struct tomoyo_io_buffer".
 103  * @ptr:        Pointer to "struct tomoyo_number_union".
 104  *
 105  * Returns true on success, false otherwise.
 106  */
 107 bool tomoyo_print_number_union(struct tomoyo_io_buffer *head,
 108                                const struct tomoyo_number_union *ptr)
 109 {
 110         unsigned long min;
 111         unsigned long max;
 112         u8 min_type;
 113         u8 max_type;
 114         if (!tomoyo_io_printf(head, " "))
 115                 return false;
 116         if (ptr->is_group)
 117                 return tomoyo_io_printf(head, "@%s",
 118                                         ptr->group->group_name->name);
 119         min_type = ptr->min_type;
 120         max_type = ptr->max_type;
 121         min = ptr->values[0];
 122         max = ptr->values[1];
 123         switch (min_type) {
 124         case TOMOYO_VALUE_TYPE_HEXADECIMAL:
 125                 if (!tomoyo_io_printf(head, "0x%lX", min))
 126                         return false;
 127                 break;
 128         case TOMOYO_VALUE_TYPE_OCTAL:
 129                 if (!tomoyo_io_printf(head, "0%lo", min))
 130                         return false;
 131                 break;
 132         default:
 133                 if (!tomoyo_io_printf(head, "%lu", min))
 134                         return false;
 135                 break;
 136         }
 137         if (min == max && min_type == max_type)
 138                 return true;
 139         switch (max_type) {
 140         case TOMOYO_VALUE_TYPE_HEXADECIMAL:
 141                 return tomoyo_io_printf(head, "-0x%lX", max);
 142         case TOMOYO_VALUE_TYPE_OCTAL:
 143                 return tomoyo_io_printf(head, "-0%lo", max);
 144         default:
 145                 return tomoyo_io_printf(head, "-%lu", max);
 146         }
 147 }
 148
 149 /**
 150  * tomoyo_io_printf - Transactional printf() to "struct tomoyo_io_buffer" structure.
 151  *
 152  * @head: Pointer to "struct tomoyo_io_buffer".
 153  * @fmt:  The printf()'s format string, followed by parameters.
 154  *
 155  * Returns true if output was written, false otherwise.
 156  *
 157  * The snprintf() will truncate, but tomoyo_io_printf() won't.
 158  */
 159 bool tomoyo_io_printf(struct tomoyo_io_buffer *head, const char *fmt, ...)
 160 {
 161         va_list args;
 162         int len;
 163         int pos = head->read_avail;
 164         int size = head->readbuf_size - pos;
 165
 166         if (size <= 0)
 167                 return false;
 168         va_start(args, fmt);
 169         len = vsnprintf(head->read_buf + pos, size, fmt, args);
 170         va_end(args);
 171         if (pos + len >= head->readbuf_size)
 172                 return false;
 173         head->read_avail += len;
 174         return true;
 175 }
 176
 177 /**
 178  * tomoyo_find_or_assign_new_profile - Create a new profile.
 179  *
 180  * @profile: Profile number to create.
 181  *
 182  * Returns pointer to "struct tomoyo_profile" on success, NULL otherwise.
 183  */
 184 static struct tomoyo_profile *tomoyo_find_or_assign_new_profile
 185 (const unsigned int profile)
 186 {
 187         struct tomoyo_profile *ptr;
 188         struct tomoyo_profile *entry;
 189         if (profile >= TOMOYO_MAX_PROFILES)
 190                 return NULL;
 191         ptr = tomoyo_profile_ptr[profile];
 192         if (ptr)
 193                 return ptr;
 194         entry = kzalloc(sizeof(*entry), GFP_NOFS);
 195         if (mutex_lock_interruptible(&tomoyo_policy_lock))
 196                 goto out;
 197         ptr = tomoyo_profile_ptr[profile];
 198         if (!ptr && tomoyo_memory_ok(entry)) {
 199                 ptr = entry;
 200                 ptr->learning = &tomoyo_default_profile.preference;
 201                 ptr->permissive = &tomoyo_default_profile.preference;
 202                 ptr->enforcing = &tomoyo_default_profile.preference;
 203                 ptr->default_config = TOMOYO_CONFIG_DISABLED;
 204                 memset(ptr->config, TOMOYO_CONFIG_USE_DEFAULT,
 205                        sizeof(ptr->config));
 206                 mb(); /* Avoid out-of-order execution. */
 207                 tomoyo_profile_ptr[profile] = ptr;
 208                 entry = NULL;
 209         }
 210         mutex_unlock(&tomoyo_policy_lock);
 211  out:
 212         kfree(entry);
 213         return ptr;
 214 }
 215
 216 /**
 217  * tomoyo_profile - Find a profile.
 218  *
 219  * @profile: Profile number to find.
 220  *
 221  * Returns pointer to "struct tomoyo_profile".
 222  */
 223 struct tomoyo_profile *tomoyo_profile(const u8 profile)
 224 {
 225         struct tomoyo_profile *ptr = tomoyo_profile_ptr[profile];
 226         if (!tomoyo_policy_loaded)
 227                 return &tomoyo_default_profile;
 228         BUG_ON(!ptr);
 229         return ptr;
 230 }
 231
 232 /**
 233  * tomoyo_write_profile - Write profile table.
 234  *
 235  * @head: Pointer to "struct tomoyo_io_buffer".
 236  *
 237  * Returns 0 on success, negative value otherwise.
 238  */
 239 static int tomoyo_write_profile(struct tomoyo_io_buffer *head)
 240 {
 241         char *data = head->write_buf;
 242         unsigned int i;
 243         int value;
 244         int mode;
 245         u8 config;
 246         bool use_default = false;
 247         char *cp;
 248         struct tomoyo_profile *profile;
 249         if (sscanf(data, "PROFILE_VERSION=%u", &tomoyo_profile_version) == 1)
 250                 return 0;
 251         i = simple_strtoul(data, &cp, 10);
 252         if (data == cp) {
 253                 profile = &tomoyo_default_profile;
 254         } else {
 255                 if (*cp != '-')
 256                         return -EINVAL;
 257                 data = cp + 1;
 258                 profile = tomoyo_find_or_assign_new_profile(i);
 259                 if (!profile)
 260                         return -EINVAL;
 261         }
 262         cp = strchr(data, '=');
 263         if (!cp)
 264                 return -EINVAL;
 265         *cp++ = '\0';
 266         if (profile != &tomoyo_default_profile)
 267                 use_default = strstr(cp, "use_default") != NULL;
 268         if (strstr(cp, "verbose=yes"))
 269                 value = 1;
 270         else if (strstr(cp, "verbose=no"))
 271                 value = 0;
 272         else
 273                 value = -1;
 274         if (!strcmp(data, "PREFERENCE::enforcing")) {
 275                 if (use_default) {
 276                         profile->enforcing = &tomoyo_default_profile.preference;
 277                         return 0;
 278                 }
 279                 profile->enforcing = &profile->preference;
 280                 if (value >= 0)
 281                         profile->preference.enforcing_verbose = value;
 282                 return 0;
 283         }
 284         if (!strcmp(data, "PREFERENCE::permissive")) {
 285                 if (use_default) {
 286                         profile->permissive = &tomoyo_default_profile.preference;
 287                         return 0;
 288                 }
 289                 profile->permissive = &profile->preference;
 290                 if (value >= 0)
 291                         profile->preference.permissive_verbose = value;
 292                 return 0;
 293         }
 294         if (!strcmp(data, "PREFERENCE::learning")) {
 295                 char *cp2;
 296                 if (use_default) {
 297                         profile->learning = &tomoyo_default_profile.preference;
 298                         return 0;
 299                 }
 300                 profile->learning = &profile->preference;
 301                 if (value >= 0)
 302                         profile->preference.learning_verbose = value;
 303                 cp2 = strstr(cp, "max_entry=");
 304                 if (cp2)
 305                         sscanf(cp2 + 10, "%u",
 306                                &profile->preference.learning_max_entry);
 307                 return 0;
 308         }
 309         if (profile == &tomoyo_default_profile)
 310                 return -EINVAL;
 311         if (!strcmp(data, "COMMENT")) {
 312                 const struct tomoyo_path_info *old_comment = profile->comment;
 313                 profile->comment = tomoyo_get_name(cp);
 314                 tomoyo_put_name(old_comment);
 315                 return 0;
 316         }
 317         if (!strcmp(data, "CONFIG")) {
 318                 i = TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX;
 319                 config = profile->default_config;
 320         } else if (tomoyo_str_starts(&data, "CONFIG::")) {
 321                 config = 0;
 322                 for (i = 0; i < TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX; i++) {
 323                         if (strcmp(data, tomoyo_mac_keywords[i]))
 324                                 continue;
 325                         config = profile->config[i];
 326                         break;
 327                 }
 328                 if (i == TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX)
 329                         return -EINVAL;
 330         } else {
 331                 return -EINVAL;
 332         }
 333         if (use_default) {
 334                 config = TOMOYO_CONFIG_USE_DEFAULT;
 335         } else {
 336                 for (mode = 3; mode >= 0; mode--)
 337                         if (strstr(cp, tomoyo_mode_4[mode]))
 338                                 /*
 339                                  * Update lower 3 bits in order to distinguish
 340                                  * 'config' from 'TOMOYO_CONFIG_USE_DEAFULT'.
 341                                  */
 342                                 config = (config & ~7) | mode;
 343         }
 344         if (i < TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX)
 345                 profile->config[i] = config;
 346         else if (config != TOMOYO_CONFIG_USE_DEFAULT)
 347                 profile->default_config = config;
 348         return 0;
 349 }
 350
 351 /**
 352  * tomoyo_read_profile - Read profile table.
 353  *
 354  * @head: Pointer to "struct tomoyo_io_buffer".
 355  */
 356 static void tomoyo_read_profile(struct tomoyo_io_buffer *head)
 357 {
 358         int index;
 359         if (head->read_eof)
 360                 return;
 361         if (head->read_bit)
 362                 goto body;
 363         tomoyo_io_printf(head, "PROFILE_VERSION=%s\n", "20090903");
 364         tomoyo_io_printf(head, "PREFERENCE::learning={ verbose=%s "
 365                          "max_entry=%u }\n",
 366                          tomoyo_yesno(tomoyo_default_profile.preference.
 367                                       learning_verbose),
 368                          tomoyo_default_profile.preference.learning_max_entry);
 369         tomoyo_io_printf(head, "PREFERENCE::permissive={ verbose=%s }\n",
 370                          tomoyo_yesno(tomoyo_default_profile.preference.
 371                                       permissive_verbose));
 372         tomoyo_io_printf(head, "PREFERENCE::enforcing={ verbose=%s }\n",
 373                          tomoyo_yesno(tomoyo_default_profile.preference.
 374                                       enforcing_verbose));
 375         head->read_bit = 1;
 376  body:
 377         for (index = head->read_step; index < TOMOYO_MAX_PROFILES; index++) {
 378                 bool done;
 379                 u8 config;
 380                 int i;
 381                 int pos;
 382                 const struct tomoyo_profile *profile
 383                         = tomoyo_profile_ptr[index];
 384                 const struct tomoyo_path_info *comment;
 385                 head->read_step = index;
 386                 if (!profile)
 387                         continue;
 388                 pos = head->read_avail;
 389                 comment = profile->comment;
 390                 done = tomoyo_io_printf(head, "%u-COMMENT=%s\n", index,
 391                                         comment ? comment->name : "");
 392                 if (!done)
 393                         goto out;
 394                 config = profile->default_config;
 395                 if (!tomoyo_io_printf(head, "%u-CONFIG={ mode=%s }\n", index,
 396                                       tomoyo_mode_4[config & 3]))
 397                         goto out;
 398                 for (i = 0; i < TOMOYO_MAX_MAC_INDEX +
 399                              TOMOYO_MAX_MAC_CATEGORY_INDEX; i++) {
 400                         config = profile->config[i];
 401                         if (config == TOMOYO_CONFIG_USE_DEFAULT)
 402                                 continue;
 403                         if (!tomoyo_io_printf(head,
 404                                               "%u-CONFIG::%s={ mode=%s }\n",
 405                                               index, tomoyo_mac_keywords[i],
 406                                               tomoyo_mode_4[config & 3]))
 407                                 goto out;
 408                 }
 409                 if (profile->learning != &tomoyo_default_profile.preference &&
 410                     !tomoyo_io_printf(head, "%u-PREFERENCE::learning={ "
 411                                       "verbose=%s max_entry=%u }\n", index,
 412                                       tomoyo_yesno(profile->preference.
 413                                                    learning_verbose),
 414                                       profile->preference.learning_max_entry))
 415                         goto out;
 416                 if (profile->permissive != &tomoyo_default_profile.preference
 417                     && !tomoyo_io_printf(head, "%u-PREFERENCE::permissive={ "
 418                                          "verbose=%s }\n", index,
 419                                          tomoyo_yesno(profile->preference.
 420                                                       permissive_verbose)))
 421                         goto out;
 422                 if (profile->enforcing != &tomoyo_default_profile.preference &&
 423                     !tomoyo_io_printf(head, "%u-PREFERENCE::enforcing={ "
 424                                       "verbose=%s }\n", index,
 425                                       tomoyo_yesno(profile->preference.
 426                                                    enforcing_verbose)))
 427                         goto out;
 428                 continue;
 429  out:
 430                 head->read_avail = pos;
 431                 break;
 432         }
 433         if (index == TOMOYO_MAX_PROFILES)
 434                 head->read_eof = true;
 435 }
 436
 437 static bool tomoyo_same_manager_entry(const struct tomoyo_acl_head *a,
 438                                       const struct tomoyo_acl_head *b)
 439 {
 440         return container_of(a, struct tomoyo_policy_manager_entry, head)
 441                 ->manager ==
 442                 container_of(b, struct tomoyo_policy_manager_entry, head)
 443                 ->manager;
 444 }
 445
 446 /**
 447  * tomoyo_update_manager_entry - Add a manager entry.
 448  *
 449  * @manager:   The path to manager or the domainnamme.
 450  * @is_delete: True if it is a delete request.
 451  *
 452  * Returns 0 on success, negative value otherwise.
 453  *
 454  * Caller holds tomoyo_read_lock().
 455  */
 456 static int tomoyo_update_manager_entry(const char *manager,
 457                                        const bool is_delete)
 458 {
 459         struct tomoyo_policy_manager_entry e = { };
 460         int error;
 461
 462         if (tomoyo_domain_def(manager)) {
 463                 if (!tomoyo_correct_domain(manager))
 464                         return -EINVAL;
 465                 e.is_domain = true;
 466         } else {
 467                 if (!tomoyo_correct_path(manager))
 468                         return -EINVAL;
 469         }
 470         e.manager = tomoyo_get_name(manager);
 471         if (!e.manager)
 472                 return -ENOMEM;
 473         error = tomoyo_update_policy(&e.head, sizeof(e), is_delete,
 474                                      &tomoyo_policy_list[TOMOYO_ID_MANAGER],
 475                                      tomoyo_same_manager_entry);
 476         tomoyo_put_name(e.manager);
 477         return error;
 478 }
 479
 480 /**
 481  * tomoyo_write_manager_policy - Write manager policy.
 482  *
 483  * @head: Pointer to "struct tomoyo_io_buffer".
 484  *
 485  * Returns 0 on success, negative value otherwise.
 486  *
 487  * Caller holds tomoyo_read_lock().
 488  */
 489 static int tomoyo_write_manager_policy(struct tomoyo_io_buffer *head)
 490 {
 491         char *data = head->write_buf;
 492         bool is_delete = tomoyo_str_starts(&data, TOMOYO_KEYWORD_DELETE);
 493
 494         if (!strcmp(data, "manage_by_non_root")) {
 495                 tomoyo_manage_by_non_root = !is_delete;
 496                 return 0;
 497         }
 498         return tomoyo_update_manager_entry(data, is_delete);
 499 }
 500
 501 /**
 502  * tomoyo_read_manager_policy - Read manager policy.
 503  *
 504  * @head: Pointer to "struct tomoyo_io_buffer".
 505  *
 506  * Caller holds tomoyo_read_lock().
 507  */
 508 static void tomoyo_read_manager_policy(struct tomoyo_io_buffer *head)
 509 {
 510         bool done = true;
 511
 512         if (head->read_eof)
 513                 return;
 514         list_for_each_cookie(head->read_var2,
 515                              &tomoyo_policy_list[TOMOYO_ID_MANAGER]) {
 516                 struct tomoyo_policy_manager_entry *ptr =
 517                         list_entry(head->read_var2, typeof(*ptr), head.list);
 518                 if (ptr->head.is_deleted)
 519                         continue;
 520                 done = tomoyo_io_printf(head, "%s\n", ptr->manager->name);
 521                 if (!done)
 522                         break;
 523         }
 524         head->read_eof = done;
 525 }
 526
 527 /**
 528  * tomoyo_policy_manager - Check whether the current process is a policy manager.
 529  *
 530  * Returns true if the current process is permitted to modify policy
 531  * via /sys/kernel/security/tomoyo/ interface.
 532  *
 533  * Caller holds tomoyo_read_lock().
 534  */
 535 static bool tomoyo_policy_manager(void)
 536 {
 537         struct tomoyo_policy_manager_entry *ptr;
 538         const char *exe;
 539         const struct task_struct *task = current;
 540         const struct tomoyo_path_info *domainname = tomoyo_domain()->domainname;
 541         bool found = false;
 542
 543         if (!tomoyo_policy_loaded)
 544                 return true;
 545         if (!tomoyo_manage_by_non_root && (task->cred->uid || task->cred->euid))
 546                 return false;
 547         list_for_each_entry_rcu(ptr, &tomoyo_policy_list[TOMOYO_ID_MANAGER],
 548                                 head.list) {
 549                 if (!ptr->head.is_deleted && ptr->is_domain
 550                     && !tomoyo_pathcmp(domainname, ptr->manager)) {
 551                         found = true;
 552                         break;
 553                 }
 554         }
 555         if (found)
 556                 return true;
 557         exe = tomoyo_get_exe();
 558         if (!exe)
 559                 return false;
 560         list_for_each_entry_rcu(ptr, &tomoyo_policy_list[TOMOYO_ID_MANAGER],
 561                                 head.list) {
 562                 if (!ptr->head.is_deleted && !ptr->is_domain
 563                     && !strcmp(exe, ptr->manager->name)) {
 564                         found = true;
 565                         break;
 566                 }
 567         }
 568         if (!found) { /* Reduce error messages. */
 569                 static pid_t last_pid;
 570                 const pid_t pid = current->pid;
 571                 if (last_pid != pid) {
 572                         printk(KERN_WARNING "%s ( %s ) is not permitted to "
 573                                "update policies.\n", domainname->name, exe);
 574                         last_pid = pid;
 575                 }
 576         }
 577         kfree(exe);
 578         return found;
 579 }
 580
 581 /**
 582  * tomoyo_select_one - Parse select command.
 583  *
 584  * @head: Pointer to "struct tomoyo_io_buffer".
 585  * @data: String to parse.
 586  *
 587  * Returns true on success, false otherwise.
 588  *
 589  * Caller holds tomoyo_read_lock().
 590  */
 591 static bool tomoyo_select_one(struct tomoyo_io_buffer *head, const char *data)
 592 {
 593         unsigned int pid;
 594         struct tomoyo_domain_info *domain = NULL;
 595         bool global_pid = false;
 596
 597         if (!strcmp(data, "allow_execute")) {
 598                 head->print_execute_only = true;
 599                 return true;
 600         }
 601         if (sscanf(data, "pid=%u", &pid) == 1 ||
 602             (global_pid = true, sscanf(data, "global-pid=%u", &pid) == 1)) {
 603                 struct task_struct *p;
 604                 rcu_read_lock();
 605                 read_lock(&tasklist_lock);
 606                 if (global_pid)
 607                         p = find_task_by_pid_ns(pid, &init_pid_ns);
 608                 else
 609                         p = find_task_by_vpid(pid);
 610                 if (p)
 611                         domain = tomoyo_real_domain(p);
 612                 read_unlock(&tasklist_lock);
 613                 rcu_read_unlock();
 614         } else if (!strncmp(data, "domain=", 7)) {
 615                 if (tomoyo_domain_def(data + 7))
 616                         domain = tomoyo_find_domain(data + 7);
 617         } else
 618                 return false;
 619         head->write_var1 = domain;
 620         /* Accessing read_buf is safe because head->io_sem is held. */
 621         if (!head->read_buf)
 622                 return true; /* Do nothing if open(O_WRONLY). */
 623         head->read_avail = 0;
 624         tomoyo_io_printf(head, "# select %s\n", data);
 625         head->read_single_domain = true;
 626         head->read_eof = !domain;
 627         head->read_var1 = &domain->list;
 628         head->read_var2 = NULL;
 629         head->read_bit = 0;
 630         head->read_step = 0;
 631         if (domain && domain->is_deleted)
 632                 tomoyo_io_printf(head, "# This is a deleted domain.\n");
 633         return true;
 634 }
 635
 636 /**
 637  * tomoyo_delete_domain - Delete a domain.
 638  *
 639  * @domainname: The name of domain.
 640  *
 641  * Returns 0.
 642  *
 643  * Caller holds tomoyo_read_lock().
 644  */
 645 static int tomoyo_delete_domain(char *domainname)
 646 {
 647         struct tomoyo_domain_info *domain;
 648         struct tomoyo_path_info name;
 649
 650         name.name = domainname;
 651         tomoyo_fill_path_info(&name);
 652         if (mutex_lock_interruptible(&tomoyo_policy_lock))
 653                 return 0;
 654         /* Is there an active domain? */
 655         list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
 656                 /* Never delete tomoyo_kernel_domain */
 657                 if (domain == &tomoyo_kernel_domain)
 658                         continue;
 659                 if (domain->is_deleted ||
 660                     tomoyo_pathcmp(domain->domainname, &name))
 661                         continue;
 662                 domain->is_deleted = true;
 663                 break;
 664         }
 665         mutex_unlock(&tomoyo_policy_lock);
 666         return 0;
 667 }
 668
 669 /**
 670  * tomoyo_write_domain_policy2 - Write domain policy.
 671  *
 672  * @head: Pointer to "struct tomoyo_io_buffer".
 673  *
 674  * Returns 0 on success, negative value otherwise.
 675  *
 676  * Caller holds tomoyo_read_lock().
 677  */
 678 static int tomoyo_write_domain_policy2(char *data,
 679                                        struct tomoyo_domain_info *domain,
 680                                        const bool is_delete)
 681 {
 682         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_ALLOW_MOUNT))
 683                 return tomoyo_write_mount_policy(data, domain, is_delete);
 684         return tomoyo_write_file_policy(data, domain, is_delete);
 685 }
 686
 687 /**
 688  * tomoyo_write_domain_policy - Write domain policy.
 689  *
 690  * @head: Pointer to "struct tomoyo_io_buffer".
 691  *
 692  * Returns 0 on success, negative value otherwise.
 693  *
 694  * Caller holds tomoyo_read_lock().
 695  */
 696 static int tomoyo_write_domain_policy(struct tomoyo_io_buffer *head)
 697 {
 698         char *data = head->write_buf;
 699         struct tomoyo_domain_info *domain = head->write_var1;
 700         bool is_delete = false;
 701         bool is_select = false;
 702         unsigned int profile;
 703
 704         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_DELETE))
 705                 is_delete = true;
 706         else if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_SELECT))
 707                 is_select = true;
 708         if (is_select && tomoyo_select_one(head, data))
 709                 return 0;
 710         /* Don't allow updating policies by non manager programs. */
 711         if (!tomoyo_policy_manager())
 712                 return -EPERM;
 713         if (tomoyo_domain_def(data)) {
 714                 domain = NULL;
 715                 if (is_delete)
 716                         tomoyo_delete_domain(data);
 717                 else if (is_select)
 718                         domain = tomoyo_find_domain(data);
 719                 else
 720                         domain = tomoyo_find_or_assign_new_domain(data, 0);
 721                 head->write_var1 = domain;
 722                 return 0;
 723         }
 724         if (!domain)
 725                 return -EINVAL;
 726
 727         if (sscanf(data, TOMOYO_KEYWORD_USE_PROFILE "%u", &profile) == 1
 728             && profile < TOMOYO_MAX_PROFILES) {
 729                 if (tomoyo_profile_ptr[profile] || !tomoyo_policy_loaded)
 730                         domain->profile = (u8) profile;
 731                 return 0;
 732         }
 733         if (!strcmp(data, TOMOYO_KEYWORD_IGNORE_GLOBAL_ALLOW_READ)) {
 734                 domain->ignore_global_allow_read = !is_delete;
 735                 return 0;
 736         }
 737         if (!strcmp(data, TOMOYO_KEYWORD_QUOTA_EXCEEDED)) {
 738                 domain->quota_warned = !is_delete;
 739                 return 0;
 740         }
 741         if (!strcmp(data, TOMOYO_KEYWORD_TRANSITION_FAILED)) {
 742                 domain->transition_failed = !is_delete;
 743                 return 0;
 744         }
 745         return tomoyo_write_domain_policy2(data, domain, is_delete);
 746 }
 747
 748 /**
 749  * tomoyo_fns - Find next set bit.
 750  *
 751  * @perm: 8 bits value.
 752  * @bit:  First bit to find.
 753  *
 754  * Returns next on-bit on success, 8 otherwise.
 755  */
 756 static u8 tomoyo_fns(const u8 perm, u8 bit)
 757 {
 758         for ( ; bit < 8; bit++)
 759                 if (perm & (1 << bit))
 760                         break;
 761         return bit;
 762 }
 763
 764 /**
 765  * tomoyo_print_entry - Print an ACL entry.
 766  *
 767  * @head: Pointer to "struct tomoyo_io_buffer".
 768  * @acl:  Pointer to an ACL entry.
 769  *
 770  * Returns true on success, false otherwise.
 771  */
 772 static bool tomoyo_print_entry(struct tomoyo_io_buffer *head,
 773                                struct tomoyo_acl_info *acl)
 774 {
 775         const u8 acl_type = acl->type;
 776         u8 bit = head->read_bit;
 777         int pos = head->read_avail;
 778
 779         if (acl->is_deleted)
 780                 return true;
 781  next:
 782         if (acl_type == TOMOYO_TYPE_PATH_ACL) {
 783                 struct tomoyo_path_acl *ptr =
 784                         container_of(acl, typeof(*ptr), head);
 785                 const u16 perm = ptr->perm;
 786                 for ( ; bit < TOMOYO_MAX_PATH_OPERATION; bit++) {
 787                         if (!(perm & (1 << bit)))
 788                                 continue;
 789                         if (head->print_execute_only &&
 790                             bit != TOMOYO_TYPE_EXECUTE)
 791                                 continue;
 792                         /* Print "read/write" instead of "read" and "write". */
 793                         if ((bit == TOMOYO_TYPE_READ ||
 794                              bit == TOMOYO_TYPE_WRITE)
 795                             && (perm & (1 << TOMOYO_TYPE_READ_WRITE)))
 796                                 continue;
 797                         break;
 798                 }
 799                 if (bit >= TOMOYO_MAX_PATH_OPERATION)
 800                         goto done;
 801                 if (!tomoyo_io_printf(head, "allow_%s ",
 802                                       tomoyo_path_keyword[bit]) ||
 803                     !tomoyo_print_name_union(head, &ptr->name))
 804                         goto out;
 805         } else if (head->print_execute_only) {
 806                 return true;
 807         } else if (acl_type == TOMOYO_TYPE_PATH2_ACL) {
 808                 struct tomoyo_path2_acl *ptr =
 809                         container_of(acl, typeof(*ptr), head);
 810                 bit = tomoyo_fns(ptr->perm, bit);
 811                 if (bit >= TOMOYO_MAX_PATH2_OPERATION)
 812                         goto done;
 813                 if (!tomoyo_io_printf(head, "allow_%s ",
 814                                       tomoyo_path2_keyword[bit]) ||
 815                     !tomoyo_print_name_union(head, &ptr->name1) ||
 816                     !tomoyo_print_name_union(head, &ptr->name2))
 817                         goto out;
 818         } else if (acl_type == TOMOYO_TYPE_PATH_NUMBER_ACL) {
 819                 struct tomoyo_path_number_acl *ptr =
 820                         container_of(acl, typeof(*ptr), head);
 821                 bit = tomoyo_fns(ptr->perm, bit);
 822                 if (bit >= TOMOYO_MAX_PATH_NUMBER_OPERATION)
 823                         goto done;
 824                 if (!tomoyo_io_printf(head, "allow_%s",
 825                                       tomoyo_path_number_keyword[bit]) ||
 826                     !tomoyo_print_name_union(head, &ptr->name) ||
 827                     !tomoyo_print_number_union(head, &ptr->number))
 828                         goto out;
 829         } else if (acl_type == TOMOYO_TYPE_MKDEV_ACL) {
 830                 struct tomoyo_mkdev_acl *ptr =
 831                         container_of(acl, typeof(*ptr), head);
 832                 bit = tomoyo_fns(ptr->perm, bit);
 833                 if (bit >= TOMOYO_MAX_MKDEV_OPERATION)
 834                         goto done;
 835                 if (!tomoyo_io_printf(head, "allow_%s",
 836                                       tomoyo_mkdev_keyword[bit]) ||
 837                     !tomoyo_print_name_union(head, &ptr->name) ||
 838                     !tomoyo_print_number_union(head, &ptr->mode) ||
 839                     !tomoyo_print_number_union(head, &ptr->major) ||
 840                     !tomoyo_print_number_union(head, &ptr->minor))
 841                         goto out;
 842         } else if (acl_type == TOMOYO_TYPE_MOUNT_ACL) {
 843                 struct tomoyo_mount_acl *ptr =
 844                         container_of(acl, typeof(*ptr), head);
 845                 if (!tomoyo_io_printf(head, TOMOYO_KEYWORD_ALLOW_MOUNT) ||
 846                     !tomoyo_print_name_union(head, &ptr->dev_name) ||
 847                     !tomoyo_print_name_union(head, &ptr->dir_name) ||
 848                     !tomoyo_print_name_union(head, &ptr->fs_type) ||
 849                     !tomoyo_print_number_union(head, &ptr->flags))
 850                         goto out;
 851         }
 852         if (!tomoyo_io_printf(head, "\n"))
 853                 goto out;
 854         head->read_bit = bit;
 855         if (acl_type != TOMOYO_TYPE_MOUNT_ACL) {
 856                 bit++;
 857                 goto next;
 858         }
 859  done:
 860         head->read_bit = 0;
 861         return true;
 862  out:
 863         head->read_avail = pos;
 864         return false;
 865 }
 866
 867 /**
 868  * tomoyo_read_domain_policy - Read domain policy.
 869  *
 870  * @head: Pointer to "struct tomoyo_io_buffer".
 871  *
 872  * Caller holds tomoyo_read_lock().
 873  */
 874 static void tomoyo_read_domain_policy(struct tomoyo_io_buffer *head)
 875 {
 876         bool done = true;
 877
 878         if (head->read_eof)
 879                 return;
 880         if (head->read_step == 0)
 881                 head->read_step = 1;
 882         list_for_each_cookie(head->read_var1, &tomoyo_domain_list) {
 883                 struct tomoyo_domain_info *domain =
 884                         list_entry(head->read_var1, typeof(*domain), list);
 885                 const char *quota_exceeded = "";
 886                 const char *transition_failed = "";
 887                 const char *ignore_global_allow_read = "";
 888                 if (head->read_step != 1)
 889                         goto acl_loop;
 890                 if (domain->is_deleted && !head->read_single_domain)
 891                         continue;
 892                 /* Print domainname and flags. */
 893                 if (domain->quota_warned)
 894                         quota_exceeded = "quota_exceeded\n";
 895                 if (domain->transition_failed)
 896                         transition_failed = "transition_failed\n";
 897                 if (domain->ignore_global_allow_read)
 898                         ignore_global_allow_read
 899                                 = TOMOYO_KEYWORD_IGNORE_GLOBAL_ALLOW_READ "\n";
 900                 done = tomoyo_io_printf(head, "%s\n" TOMOYO_KEYWORD_USE_PROFILE
 901                                         "%u\n%s%s%s\n",
 902                                         domain->domainname->name,
 903                                         domain->profile, quota_exceeded,
 904                                         transition_failed,
 905                                         ignore_global_allow_read);
 906                 if (!done)
 907                         break;
 908                 head->read_step = 2;
 909 acl_loop:
 910                 if (head->read_step == 3)
 911                         goto tail_mark;
 912                 /* Print ACL entries in the domain. */
 913                 list_for_each_cookie(head->read_var2,
 914                                      &domain->acl_info_list) {
 915                         struct tomoyo_acl_info *ptr =
 916                                 list_entry(head->read_var2, typeof(*ptr), list);
 917                         done = tomoyo_print_entry(head, ptr);
 918                         if (!done)
 919                                 break;
 920                 }
 921                 if (!done)
 922                         break;
 923                 head->read_var2 = NULL;
 924                 head->read_step = 3;
 925 tail_mark:
 926                 done = tomoyo_io_printf(head, "\n");
 927                 if (!done)
 928                         break;
 929                 head->read_step = 1;
 930                 if (head->read_single_domain)
 931                         break;
 932         }
 933         head->read_eof = done;
 934 }
 935
 936 /**
 937  * tomoyo_write_domain_profile - Assign profile for specified domain.
 938  *
 939  * @head: Pointer to "struct tomoyo_io_buffer".
 940  *
 941  * Returns 0 on success, -EINVAL otherwise.
 942  *
 943  * This is equivalent to doing
 944  *
 945  *     ( echo "select " $domainname; echo "use_profile " $profile ) |
 946  *     /usr/sbin/tomoyo-loadpolicy -d
 947  *
 948  * Caller holds tomoyo_read_lock().
 949  */
 950 static int tomoyo_write_domain_profile(struct tomoyo_io_buffer *head)
 951 {
 952         char *data = head->write_buf;
 953         char *cp = strchr(data, ' ');
 954         struct tomoyo_domain_info *domain;
 955         unsigned long profile;
 956
 957         if (!cp)
 958                 return -EINVAL;
 959         *cp = '\0';
 960         domain = tomoyo_find_domain(cp + 1);
 961         if (strict_strtoul(data, 10, &profile))
 962                 return -EINVAL;
 963         if (domain && profile < TOMOYO_MAX_PROFILES
 964             && (tomoyo_profile_ptr[profile] || !tomoyo_policy_loaded))
 965                 domain->profile = (u8) profile;
 966         return 0;
 967 }
 968
 969 /**
 970  * tomoyo_read_domain_profile - Read only domainname and profile.
 971  *
 972  * @head: Pointer to "struct tomoyo_io_buffer".
 973  *
 974  * Returns list of profile number and domainname pairs.
 975  *
 976  * This is equivalent to doing
 977  *
 978  *     grep -A 1 '^<kernel>' /sys/kernel/security/tomoyo/domain_policy |
 979  *     awk ' { if ( domainname == "" ) { if ( $1 == "<kernel>" )
 980  *     domainname = $0; } else if ( $1 == "use_profile" ) {
 981  *     print $2 " " domainname; domainname = ""; } } ; '
 982  *
 983  * Caller holds tomoyo_read_lock().
 984  */
 985 static void tomoyo_read_domain_profile(struct tomoyo_io_buffer *head)
 986 {
 987         bool done = true;
 988
 989         if (head->read_eof)
 990                 return;
 991         list_for_each_cookie(head->read_var1, &tomoyo_domain_list) {
 992                 struct tomoyo_domain_info *domain =
 993                         list_entry(head->read_var1, typeof(*domain), list);
 994                 if (domain->is_deleted)
 995                         continue;
 996                 done = tomoyo_io_printf(head, "%u %s\n", domain->profile,
 997                                         domain->domainname->name);
 998                 if (!done)
 999                         break;
1000         }
1001         head->read_eof = done;
1002 }
1003
1004 /**
1005  * tomoyo_write_pid: Specify PID to obtain domainname.
1006  *
1007  * @head: Pointer to "struct tomoyo_io_buffer".
1008  *
1009  * Returns 0.
1010  */
1011 static int tomoyo_write_pid(struct tomoyo_io_buffer *head)
1012 {
1013         unsigned long pid;
1014         /* No error check. */
1015         strict_strtoul(head->write_buf, 10, &pid);
1016         head->read_step = (int) pid;
1017         head->read_eof = false;
1018         return 0;
1019 }
1020
1021 /**
1022  * tomoyo_read_pid - Get domainname of the specified PID.
1023  *
1024  * @head: Pointer to "struct tomoyo_io_buffer".
1025  *
1026  * Returns the domainname which the specified PID is in on success,
1027  * empty string otherwise.
1028  * The PID is specified by tomoyo_write_pid() so that the user can obtain
1029  * using read()/write() interface rather than sysctl() interface.
1030  */
1031 static void tomoyo_read_pid(struct tomoyo_io_buffer *head)
1032 {
1033         if (head->read_avail == 0 && !head->read_eof) {
1034                 const int pid = head->read_step;
1035                 struct task_struct *p;
1036                 struct tomoyo_domain_info *domain = NULL;
1037                 rcu_read_lock();
1038                 read_lock(&tasklist_lock);
1039                 p = find_task_by_vpid(pid);
1040                 if (p)
1041                         domain = tomoyo_real_domain(p);
1042                 read_unlock(&tasklist_lock);
1043                 rcu_read_unlock();
1044                 if (domain)
1045                         tomoyo_io_printf(head, "%d %u %s", pid, domain->profile,
1046                                          domain->domainname->name);
1047                 head->read_eof = true;
1048         }
1049 }
1050
1051 static const char *tomoyo_transition_type[TOMOYO_MAX_TRANSITION_TYPE] = {
1052         [TOMOYO_TRANSITION_CONTROL_NO_INITIALIZE]
1053         = TOMOYO_KEYWORD_NO_INITIALIZE_DOMAIN,
1054         [TOMOYO_TRANSITION_CONTROL_INITIALIZE]
1055         = TOMOYO_KEYWORD_INITIALIZE_DOMAIN,
1056         [TOMOYO_TRANSITION_CONTROL_NO_KEEP] = TOMOYO_KEYWORD_NO_KEEP_DOMAIN,
1057         [TOMOYO_TRANSITION_CONTROL_KEEP] = TOMOYO_KEYWORD_KEEP_DOMAIN
1058 };
1059
1060 /**
1061  * tomoyo_write_exception_policy - Write exception policy.
1062  *
1063  * @head: Pointer to "struct tomoyo_io_buffer".
1064  *
1065  * Returns 0 on success, negative value otherwise.
1066  *
1067  * Caller holds tomoyo_read_lock().
1068  */
1069 static int tomoyo_write_exception_policy(struct tomoyo_io_buffer *head)
1070 {
1071         char *data = head->write_buf;
1072         bool is_delete = tomoyo_str_starts(&data, TOMOYO_KEYWORD_DELETE);
1073         u8 i;
1074
1075         for (i = 0; i < TOMOYO_MAX_TRANSITION_TYPE; i++) {
1076                 if (tomoyo_str_starts(&data, tomoyo_transition_type[i]))
1077                         return tomoyo_write_transition_control(data, is_delete,
1078                                                                i);
1079         }
1080         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_AGGREGATOR))
1081                 return tomoyo_write_aggregator_policy(data, is_delete);
1082         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_ALLOW_READ))
1083                 return tomoyo_write_globally_readable_policy(data, is_delete);
1084         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_FILE_PATTERN))
1085                 return tomoyo_write_pattern_policy(data, is_delete);
1086         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_DENY_REWRITE))
1087                 return tomoyo_write_no_rewrite_policy(data, is_delete);
1088         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_PATH_GROUP))
1089                 return tomoyo_write_group(data, is_delete, TOMOYO_PATH_GROUP);
1090         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_NUMBER_GROUP))
1091                 return tomoyo_write_group(data, is_delete, TOMOYO_NUMBER_GROUP);
1092         return -EINVAL;
1093 }
1094
1095 static void tomoyo_print_number(char *buffer, int buffer_len,
1096                              const struct tomoyo_number_union *ptr)
1097 {
1098         int i;
1099         unsigned long min = ptr->values[0];
1100         const unsigned long max = ptr->values[1];
1101         u8 min_type = ptr->min_type;
1102         const u8 max_type = ptr->max_type;
1103         memset(buffer, 0, buffer_len);
1104         buffer_len -= 2;
1105         for (i = 0; i < 2; i++) {
1106                 int len;
1107                 switch (min_type) {
1108                 case TOMOYO_VALUE_TYPE_HEXADECIMAL:
1109                         snprintf(buffer, buffer_len, "0x%lX", min);
1110                         break;
1111                 case TOMOYO_VALUE_TYPE_OCTAL:
1112                         snprintf(buffer, buffer_len, "0%lo", min);
1113                         break;
1114                 default:
1115                         snprintf(buffer, buffer_len, "%lu", min);
1116                         break;
1117                 }
1118                 if (min == max && min_type == max_type)
1119                         break;
1120                 len = strlen(buffer);
1121                 buffer[len++] = '-';
1122                 buffer += len;
1123                 buffer_len -= len;
1124                 min_type = max_type;
1125                 min = max;
1126         }
1127 }
1128
1129 static const char *tomoyo_group_name[TOMOYO_MAX_GROUP] = {
1130         [TOMOYO_PATH_GROUP] = TOMOYO_KEYWORD_PATH_GROUP,
1131         [TOMOYO_NUMBER_GROUP] = TOMOYO_KEYWORD_NUMBER_GROUP
1132 };
1133
1134 /**
1135  * tomoyo_read_group - Read "struct tomoyo_path_group"/"struct tomoyo_number_group" list.
1136  *
1137  * @head: Pointer to "struct tomoyo_io_buffer".
1138  * @idx:  Index number.
1139  *
1140  * Returns true on success, false otherwise.
1141  *
1142  * Caller holds tomoyo_read_lock().
1143  */
1144 static bool tomoyo_read_group(struct tomoyo_io_buffer *head, const int idx)
1145 {
1146         const char *w[3] = { "", "", "" };
1147         w[0] = tomoyo_group_name[idx];
1148         list_for_each_cookie(head->read_var1, &tomoyo_group_list[idx]) {
1149                 struct tomoyo_group *group =
1150                         list_entry(head->read_var1, typeof(*group), list);
1151                 w[1] = group->group_name->name;
1152                 list_for_each_cookie(head->read_var2, &group->member_list) {
1153                         char buffer[128];
1154                         struct tomoyo_acl_head *ptr =
1155                                 list_entry(head->read_var2, typeof(*ptr), list);
1156                         if (ptr->is_deleted)
1157                                 continue;
1158                         if (idx == TOMOYO_PATH_GROUP) {
1159                                 w[2] = container_of(ptr,
1160                                                     struct tomoyo_path_group,
1161                                                     head)->member_name->name;
1162                         } else if (idx == TOMOYO_NUMBER_GROUP) {
1163                                 tomoyo_print_number(buffer, sizeof(buffer),
1164                                                     &container_of
1165                                                     (ptr, struct
1166                                                      tomoyo_number_group,
1167                                                      head)->number);
1168                                 w[2] = buffer;
1169                         }
1170                         if (!tomoyo_io_printf(head, "%s%s %s\n", w[0], w[1],
1171                                               w[2]))
1172                                 return false;
1173                 }
1174                 head->read_var2 = NULL;
1175         }
1176         head->read_var1 = NULL;
1177         return true;
1178 }
1179
1180 /**
1181  * tomoyo_read_policy - Read "struct tomoyo_..._entry" list.
1182  *
1183  * @head: Pointer to "struct tomoyo_io_buffer".
1184  * @idx:  Index number.
1185  *
1186  * Returns true on success, false otherwise.
1187  *
1188  * Caller holds tomoyo_read_lock().
1189  */
1190 static bool tomoyo_read_policy(struct tomoyo_io_buffer *head, const int idx)
1191 {
1192         list_for_each_cookie(head->read_var2, &tomoyo_policy_list[idx]) {
1193                 const char *w[4] = { "", "", "", "" };
1194                 struct tomoyo_acl_head *acl =
1195                         container_of(head->read_var2, typeof(*acl), list);
1196                 if (acl->is_deleted)
1197                         continue;
1198                 switch (idx) {
1199                 case TOMOYO_ID_TRANSITION_CONTROL:
1200                         {
1201                                 struct tomoyo_transition_control *ptr =
1202                                         container_of(acl, typeof(*ptr), head);
1203                                 w[0] = tomoyo_transition_type[ptr->type];
1204                                 if (ptr->program)
1205                                         w[1] = ptr->program->name;
1206                                 if (ptr->domainname)
1207                                         w[3] = ptr->domainname->name;
1208                                 if (w[1][0] && w[3][0])
1209                                         w[2] = " from ";
1210                         }
1211                         break;
1212                 case TOMOYO_ID_GLOBALLY_READABLE:
1213                         {
1214                                 struct tomoyo_globally_readable_file_entry *ptr
1215                                         = container_of(acl, typeof(*ptr), head);
1216                                 w[0] = TOMOYO_KEYWORD_ALLOW_READ;
1217                                 w[1] = ptr->filename->name;
1218                         }
1219                         break;
1220                 case TOMOYO_ID_AGGREGATOR:
1221                         {
1222                                 struct tomoyo_aggregator_entry *ptr =
1223                                         container_of(acl, typeof(*ptr), head);
1224                                 w[0] = TOMOYO_KEYWORD_AGGREGATOR;
1225                                 w[1] = ptr->original_name->name;
1226                                 w[2] = " ";
1227                                 w[3] = ptr->aggregated_name->name;
1228                         }
1229                         break;
1230                 case TOMOYO_ID_PATTERN:
1231                         {
1232                                 struct tomoyo_pattern_entry *ptr =
1233                                         container_of(acl, typeof(*ptr), head);
1234                                 w[0] = TOMOYO_KEYWORD_FILE_PATTERN;
1235                                 w[1] = ptr->pattern->name;
1236                         }
1237                         break;
1238                 case TOMOYO_ID_NO_REWRITE:
1239                         {
1240                                 struct tomoyo_no_rewrite_entry *ptr =
1241                                         container_of(acl, typeof(*ptr), head);
1242                                 w[0] = TOMOYO_KEYWORD_DENY_REWRITE;
1243                                 w[1] = ptr->pattern->name;
1244                         }
1245                         break;
1246                 default:
1247                         continue;
1248                 }
1249                 if (!tomoyo_io_printf(head, "%s%s%s%s\n", w[0], w[1], w[2],
1250                                       w[3]))
1251                         return false;
1252         }
1253         head->read_var2 = NULL;
1254         return true;
1255 }
1256
1257 /**
1258  * tomoyo_read_exception_policy - Read exception policy.
1259  *
1260  * @head: Pointer to "struct tomoyo_io_buffer".
1261  *
1262  * Caller holds tomoyo_read_lock().
1263  */
1264 static void tomoyo_read_exception_policy(struct tomoyo_io_buffer *head)
1265 {
1266         if (head->read_eof)
1267                 return;
1268         while (head->read_step < TOMOYO_MAX_POLICY &&
1269                tomoyo_read_policy(head, head->read_step))
1270                 head->read_step++;
1271         if (head->read_step < TOMOYO_MAX_POLICY)
1272                 return;
1273         while (head->read_step < TOMOYO_MAX_POLICY + TOMOYO_MAX_GROUP &&
1274                tomoyo_read_group(head, head->read_step - TOMOYO_MAX_POLICY))
1275                 head->read_step++;
1276         if (head->read_step < TOMOYO_MAX_POLICY + TOMOYO_MAX_GROUP)
1277                 return;
1278         head->read_eof = true;
1279 }
1280
1281 /**
1282  * tomoyo_print_header - Get header line of audit log.
1283  *
1284  * @r: Pointer to "struct tomoyo_request_info".
1285  *
1286  * Returns string representation.
1287  *
1288  * This function uses kmalloc(), so caller must kfree() if this function
1289  * didn't return NULL.
1290  */
1291 static char *tomoyo_print_header(struct tomoyo_request_info *r)
1292 {
1293         static const char *tomoyo_mode_4[4] = {
1294                 "disabled", "learning", "permissive", "enforcing"
1295         };
1296         struct timeval tv;
1297         const pid_t gpid = task_pid_nr(current);
1298         static const int tomoyo_buffer_len = 4096;
1299         char *buffer = kmalloc(tomoyo_buffer_len, GFP_NOFS);
1300         if (!buffer)
1301                 return NULL;
1302         do_gettimeofday(&tv);
1303         snprintf(buffer, tomoyo_buffer_len - 1,
1304                  "#timestamp=%lu profile=%u mode=%s (global-pid=%u)"
1305                  " task={ pid=%u ppid=%u uid=%u gid=%u euid=%u"
1306                  " egid=%u suid=%u sgid=%u fsuid=%u fsgid=%u }",
1307                  tv.tv_sec, r->profile, tomoyo_mode_4[r->mode], gpid,
1308                  (pid_t) sys_getpid(), (pid_t) sys_getppid(),
1309                  current_uid(), current_gid(), current_euid(),
1310                  current_egid(), current_suid(), current_sgid(),
1311                  current_fsuid(), current_fsgid());
1312         return buffer;
1313 }
1314
1315 /**
1316  * tomoyo_init_audit_log - Allocate buffer for audit logs.
1317  *
1318  * @len: Required size.
1319  * @r:   Pointer to "struct tomoyo_request_info".
1320  *
1321  * Returns pointer to allocated memory.
1322  *
1323  * The @len is updated to add the header lines' size on success.
1324  *
1325  * This function uses kzalloc(), so caller must kfree() if this function
1326  * didn't return NULL.
1327  */
1328 static char *tomoyo_init_audit_log(int *len, struct tomoyo_request_info *r)
1329 {
1330         char *buf = NULL;
1331         const char *header;
1332         const char *domainname;
1333         if (!r->domain)
1334                 r->domain = tomoyo_domain();
1335         domainname = r->domain->domainname->name;
1336         header = tomoyo_print_header(r);
1337         if (!header)
1338                 return NULL;
1339         *len += strlen(domainname) + strlen(header) + 10;
1340         buf = kzalloc(*len, GFP_NOFS);
1341         if (buf)
1342                 snprintf(buf, (*len) - 1, "%s\n%s\n", header, domainname);
1343         kfree(header);
1344         return buf;
1345 }
1346
1347 /* Wait queue for tomoyo_query_list. */
1348 static DECLARE_WAIT_QUEUE_HEAD(tomoyo_query_wait);
1349
1350 /* Lock for manipulating tomoyo_query_list. */
1351 static DEFINE_SPINLOCK(tomoyo_query_list_lock);
1352
1353 /* Structure for query. */
1354 struct tomoyo_query_entry {
1355         struct list_head list;
1356         char *query;
1357         int query_len;
1358         unsigned int serial;
1359         int timer;
1360         int answer;
1361 };
1362
1363 /* The list for "struct tomoyo_query_entry". */
1364 static LIST_HEAD(tomoyo_query_list);
1365
1366 /*
1367  * Number of "struct file" referring /sys/kernel/security/tomoyo/query
1368  * interface.
1369  */
1370 static atomic_t tomoyo_query_observers = ATOMIC_INIT(0);
1371
1372 /**
1373  * tomoyo_supervisor - Ask for the supervisor's decision.
1374  *
1375  * @r:       Pointer to "struct tomoyo_request_info".
1376  * @fmt:     The printf()'s format string, followed by parameters.
1377  *
1378  * Returns 0 if the supervisor decided to permit the access request which
1379  * violated the policy in enforcing mode, TOMOYO_RETRY_REQUEST if the
1380  * supervisor decided to retry the access request which violated the policy in
1381  * enforcing mode, 0 if it is not in enforcing mode, -EPERM otherwise.
1382  */
1383 int tomoyo_supervisor(struct tomoyo_request_info *r, const char *fmt, ...)
1384 {
1385         va_list args;
1386         int error = -EPERM;
1387         int pos;
1388         int len;
1389         static unsigned int tomoyo_serial;
1390         struct tomoyo_query_entry *tomoyo_query_entry = NULL;
1391         bool quota_exceeded = false;
1392         char *header;
1393         switch (r->mode) {
1394                 char *buffer;
1395         case TOMOYO_CONFIG_LEARNING:
1396                 if (!tomoyo_domain_quota_is_ok(r))
1397                         return 0;
1398                 va_start(args, fmt);
1399                 len = vsnprintf((char *) &pos, sizeof(pos) - 1, fmt, args) + 4;
1400                 va_end(args);
1401                 buffer = kmalloc(len, GFP_NOFS);
1402                 if (!buffer)
1403                         return 0;
1404                 va_start(args, fmt);
1405                 vsnprintf(buffer, len - 1, fmt, args);
1406                 va_end(args);
1407                 tomoyo_normalize_line(buffer);
1408                 tomoyo_write_domain_policy2(buffer, r->domain, false);
1409                 kfree(buffer);
1410                 /* fall through */
1411         case TOMOYO_CONFIG_PERMISSIVE:
1412                 return 0;
1413         }
1414         if (!r->domain)
1415                 r->domain = tomoyo_domain();
1416         if (!atomic_read(&tomoyo_query_observers))
1417                 return -EPERM;
1418         va_start(args, fmt);
1419         len = vsnprintf((char *) &pos, sizeof(pos) - 1, fmt, args) + 32;
1420         va_end(args);
1421         header = tomoyo_init_audit_log(&len, r);
1422         if (!header)
1423                 goto out;
1424         tomoyo_query_entry = kzalloc(sizeof(*tomoyo_query_entry), GFP_NOFS);
1425         if (!tomoyo_query_entry)
1426                 goto out;
1427         tomoyo_query_entry->query = kzalloc(len, GFP_NOFS);
1428         if (!tomoyo_query_entry->query)
1429                 goto out;
1430         len = ksize(tomoyo_query_entry->query);
1431         INIT_LIST_HEAD(&tomoyo_query_entry->list);
1432         spin_lock(&tomoyo_query_list_lock);
1433         if (tomoyo_quota_for_query && tomoyo_query_memory_size + len +
1434             sizeof(*tomoyo_query_entry) >= tomoyo_quota_for_query) {
1435                 quota_exceeded = true;
1436         } else {
1437                 tomoyo_query_memory_size += len + sizeof(*tomoyo_query_entry);
1438                 tomoyo_query_entry->serial = tomoyo_serial++;
1439         }
1440         spin_unlock(&tomoyo_query_list_lock);
1441         if (quota_exceeded)
1442                 goto out;
1443         pos = snprintf(tomoyo_query_entry->query, len - 1, "Q%u-%hu\n%s",
1444                        tomoyo_query_entry->serial, r->retry, header);
1445         kfree(header);
1446         header = NULL;
1447         va_start(args, fmt);
1448         vsnprintf(tomoyo_query_entry->query + pos, len - 1 - pos, fmt, args);
1449         tomoyo_query_entry->query_len = strlen(tomoyo_query_entry->query) + 1;
1450         va_end(args);
1451         spin_lock(&tomoyo_query_list_lock);
1452         list_add_tail(&tomoyo_query_entry->list, &tomoyo_query_list);
1453         spin_unlock(&tomoyo_query_list_lock);
1454         /* Give 10 seconds for supervisor's opinion. */
1455         for (tomoyo_query_entry->timer = 0;
1456              atomic_read(&tomoyo_query_observers) && tomoyo_query_entry->timer < 100;
1457              tomoyo_query_entry->timer++) {
1458                 wake_up(&tomoyo_query_wait);
1459                 set_current_state(TASK_INTERRUPTIBLE);
1460                 schedule_timeout(HZ / 10);
1461                 if (tomoyo_query_entry->answer)
1462                         break;
1463         }
1464         spin_lock(&tomoyo_query_list_lock);
1465         list_del(&tomoyo_query_entry->list);
1466         tomoyo_query_memory_size -= len + sizeof(*tomoyo_query_entry);
1467         spin_unlock(&tomoyo_query_list_lock);
1468         switch (tomoyo_query_entry->answer) {
1469         case 3: /* Asked to retry by administrator. */
1470                 error = TOMOYO_RETRY_REQUEST;
1471                 r->retry++;
1472                 break;
1473         case 1:
1474                 /* Granted by administrator. */
1475                 error = 0;
1476                 break;
1477         case 0:
1478                 /* Timed out. */
1479                 break;
1480         default:
1481                 /* Rejected by administrator. */
1482                 break;
1483         }
1484  out:
1485         if (tomoyo_query_entry)
1486                 kfree(tomoyo_query_entry->query);
1487         kfree(tomoyo_query_entry);
1488         kfree(header);
1489         return error;
1490 }
1491
1492 /**
1493  * tomoyo_poll_query - poll() for /sys/kernel/security/tomoyo/query.
1494  *
1495  * @file: Pointer to "struct file".
1496  * @wait: Pointer to "poll_table".
1497  *
1498  * Returns POLLIN | POLLRDNORM when ready to read, 0 otherwise.
1499  *
1500  * Waits for access requests which violated policy in enforcing mode.
1501  */
1502 static int tomoyo_poll_query(struct file *file, poll_table *wait)
1503 {
1504         struct list_head *tmp;
1505         bool found = false;
1506         u8 i;
1507         for (i = 0; i < 2; i++) {
1508                 spin_lock(&tomoyo_query_list_lock);
1509                 list_for_each(tmp, &tomoyo_query_list) {
1510                         struct tomoyo_query_entry *ptr
1511                                 = list_entry(tmp, struct tomoyo_query_entry,
1512                                              list);
1513                         if (ptr->answer)
1514                                 continue;
1515                         found = true;
1516                         break;
1517                 }
1518                 spin_unlock(&tomoyo_query_list_lock);
1519                 if (found)
1520                         return POLLIN | POLLRDNORM;
1521                 if (i)
1522                         break;
1523                 poll_wait(file, &tomoyo_query_wait, wait);
1524         }
1525         return 0;
1526 }
1527
1528 /**
1529  * tomoyo_read_query - Read access requests which violated policy in enforcing mode.
1530  *
1531  * @head: Pointer to "struct tomoyo_io_buffer".
1532  */
1533 static void tomoyo_read_query(struct tomoyo_io_buffer *head)
1534 {
1535         struct list_head *tmp;
1536         int pos = 0;
1537         int len = 0;
1538         char *buf;
1539         if (head->read_avail)
1540                 return;
1541         if (head->read_buf) {
1542                 kfree(head->read_buf);
1543                 head->read_buf = NULL;
1544                 head->readbuf_size = 0;
1545         }
1546         spin_lock(&tomoyo_query_list_lock);
1547         list_for_each(tmp, &tomoyo_query_list) {
1548                 struct tomoyo_query_entry *ptr
1549                         = list_entry(tmp, struct tomoyo_query_entry, list);
1550                 if (ptr->answer)
1551                         continue;
1552                 if (pos++ != head->read_step)
1553                         continue;
1554                 len = ptr->query_len;
1555                 break;
1556         }
1557         spin_unlock(&tomoyo_query_list_lock);
1558         if (!len) {
1559                 head->read_step = 0;
1560                 return;
1561         }
1562         buf = kzalloc(len, GFP_NOFS);
1563         if (!buf)
1564                 return;
1565         pos = 0;
1566         spin_lock(&tomoyo_query_list_lock);
1567         list_for_each(tmp, &tomoyo_query_list) {
1568                 struct tomoyo_query_entry *ptr
1569                         = list_entry(tmp, struct tomoyo_query_entry, list);
1570                 if (ptr->answer)
1571                         continue;
1572                 if (pos++ != head->read_step)
1573                         continue;
1574                 /*
1575                  * Some query can be skipped because tomoyo_query_list
1576                  * can change, but I don't care.
1577                  */
1578                 if (len == ptr->query_len)
1579                         memmove(buf, ptr->query, len);
1580                 break;
1581         }
1582         spin_unlock(&tomoyo_query_list_lock);
1583         if (buf[0]) {
1584                 head->read_avail = len;
1585                 head->readbuf_size = head->read_avail;
1586                 head->read_buf = buf;
1587                 head->read_step++;
1588         } else {
1589                 kfree(buf);
1590         }
1591 }
1592
1593 /**
1594  * tomoyo_write_answer - Write the supervisor's decision.
1595  *
1596  * @head: Pointer to "struct tomoyo_io_buffer".
1597  *
1598  * Returns 0 on success, -EINVAL otherwise.
1599  */
1600 static int tomoyo_write_answer(struct tomoyo_io_buffer *head)
1601 {
1602         char *data = head->write_buf;
1603         struct list_head *tmp;
1604         unsigned int serial;
1605         unsigned int answer;
1606         spin_lock(&tomoyo_query_list_lock);
1607         list_for_each(tmp, &tomoyo_query_list) {
1608                 struct tomoyo_query_entry *ptr
1609                         = list_entry(tmp, struct tomoyo_query_entry, list);
1610                 ptr->timer = 0;
1611         }
1612         spin_unlock(&tomoyo_query_list_lock);
1613         if (sscanf(data, "A%u=%u", &serial, &answer) != 2)
1614                 return -EINVAL;
1615         spin_lock(&tomoyo_query_list_lock);
1616         list_for_each(tmp, &tomoyo_query_list) {
1617                 struct tomoyo_query_entry *ptr
1618                         = list_entry(tmp, struct tomoyo_query_entry, list);
1619                 if (ptr->serial != serial)
1620                         continue;
1621                 if (!ptr->answer)
1622                         ptr->answer = answer;
1623                 break;
1624         }
1625         spin_unlock(&tomoyo_query_list_lock);
1626         return 0;
1627 }
1628
1629 /**
1630  * tomoyo_read_version: Get version.
1631  *
1632  * @head: Pointer to "struct tomoyo_io_buffer".
1633  *
1634  * Returns version information.
1635  */
1636 static void tomoyo_read_version(struct tomoyo_io_buffer *head)
1637 {
1638         if (!head->read_eof) {
1639                 tomoyo_io_printf(head, "2.3.0-pre");
1640                 head->read_eof = true;
1641         }
1642 }
1643
1644 /**
1645  * tomoyo_read_self_domain - Get the current process's domainname.
1646  *
1647  * @head: Pointer to "struct tomoyo_io_buffer".
1648  *
1649  * Returns the current process's domainname.
1650  */
1651 static void tomoyo_read_self_domain(struct tomoyo_io_buffer *head)
1652 {
1653         if (!head->read_eof) {
1654                 /*
1655                  * tomoyo_domain()->domainname != NULL
1656                  * because every process belongs to a domain and
1657                  * the domain's name cannot be NULL.
1658                  */
1659                 tomoyo_io_printf(head, "%s", tomoyo_domain()->domainname->name);
1660                 head->read_eof = true;
1661         }
1662 }
1663
1664 /**
1665  * tomoyo_open_control - open() for /sys/kernel/security/tomoyo/ interface.
1666  *
1667  * @type: Type of interface.
1668  * @file: Pointer to "struct file".
1669  *
1670  * Associates policy handler and returns 0 on success, -ENOMEM otherwise.
1671  *
1672  * Caller acquires tomoyo_read_lock().
1673  */
1674 int tomoyo_open_control(const u8 type, struct file *file)
1675 {
1676         struct tomoyo_io_buffer *head = kzalloc(sizeof(*head), GFP_NOFS);
1677
1678         if (!head)
1679                 return -ENOMEM;
1680         mutex_init(&head->io_sem);
1681         head->type = type;
1682         switch (type) {
1683         case TOMOYO_DOMAINPOLICY:
1684                 /* /sys/kernel/security/tomoyo/domain_policy */
1685                 head->write = tomoyo_write_domain_policy;
1686                 head->read = tomoyo_read_domain_policy;
1687                 break;
1688         case TOMOYO_EXCEPTIONPOLICY:
1689                 /* /sys/kernel/security/tomoyo/exception_policy */
1690                 head->write = tomoyo_write_exception_policy;
1691                 head->read = tomoyo_read_exception_policy;
1692                 break;
1693         case TOMOYO_SELFDOMAIN:
1694                 /* /sys/kernel/security/tomoyo/self_domain */
1695                 head->read = tomoyo_read_self_domain;
1696                 break;
1697         case TOMOYO_DOMAIN_STATUS:
1698                 /* /sys/kernel/security/tomoyo/.domain_status */
1699                 head->write = tomoyo_write_domain_profile;
1700                 head->read = tomoyo_read_domain_profile;
1701                 break;
1702         case TOMOYO_PROCESS_STATUS:
1703                 /* /sys/kernel/security/tomoyo/.process_status */
1704                 head->write = tomoyo_write_pid;
1705                 head->read = tomoyo_read_pid;
1706                 break;
1707         case TOMOYO_VERSION:
1708                 /* /sys/kernel/security/tomoyo/version */
1709                 head->read = tomoyo_read_version;
1710                 head->readbuf_size = 128;
1711                 break;
1712         case TOMOYO_MEMINFO:
1713                 /* /sys/kernel/security/tomoyo/meminfo */
1714                 head->write = tomoyo_write_memory_quota;
1715                 head->read = tomoyo_read_memory_counter;
1716                 head->readbuf_size = 512;
1717                 break;
1718         case TOMOYO_PROFILE:
1719                 /* /sys/kernel/security/tomoyo/profile */
1720                 head->write = tomoyo_write_profile;
1721                 head->read = tomoyo_read_profile;
1722                 break;
1723         case TOMOYO_QUERY: /* /sys/kernel/security/tomoyo/query */
1724                 head->poll = tomoyo_poll_query;
1725                 head->write = tomoyo_write_answer;
1726                 head->read = tomoyo_read_query;
1727                 break;
1728         case TOMOYO_MANAGER:
1729                 /* /sys/kernel/security/tomoyo/manager */
1730                 head->write = tomoyo_write_manager_policy;
1731                 head->read = tomoyo_read_manager_policy;
1732                 break;
1733         }
1734         if (!(file->f_mode & FMODE_READ)) {
1735                 /*
1736                  * No need to allocate read_buf since it is not opened
1737                  * for reading.
1738                  */
1739                 head->read = NULL;
1740                 head->poll = NULL;
1741         } else if (!head->poll) {
1742                 /* Don't allocate read_buf for poll() access. */
1743                 if (!head->readbuf_size)
1744                         head->readbuf_size = 4096 * 2;
1745                 head->read_buf = kzalloc(head->readbuf_size, GFP_NOFS);
1746                 if (!head->read_buf) {
1747                         kfree(head);
1748                         return -ENOMEM;
1749                 }
1750         }
1751         if (!(file->f_mode & FMODE_WRITE)) {
1752                 /*
1753                  * No need to allocate write_buf since it is not opened
1754                  * for writing.
1755                  */
1756                 head->write = NULL;
1757         } else if (head->write) {
1758                 head->writebuf_size = 4096 * 2;
1759                 head->write_buf = kzalloc(head->writebuf_size, GFP_NOFS);
1760                 if (!head->write_buf) {
1761                         kfree(head->read_buf);
1762                         kfree(head);
1763                         return -ENOMEM;
1764                 }
1765         }
1766         if (type != TOMOYO_QUERY)
1767                 head->reader_idx = tomoyo_read_lock();
1768         file->private_data = head;
1769         /*
1770          * Call the handler now if the file is
1771          * /sys/kernel/security/tomoyo/self_domain
1772          * so that the user can use
1773          * cat < /sys/kernel/security/tomoyo/self_domain"
1774          * to know the current process's domainname.
1775          */
1776         if (type == TOMOYO_SELFDOMAIN)
1777                 tomoyo_read_control(file, NULL, 0);
1778         /*
1779          * If the file is /sys/kernel/security/tomoyo/query , increment the
1780          * observer counter.
1781          * The obserber counter is used by tomoyo_supervisor() to see if
1782          * there is some process monitoring /sys/kernel/security/tomoyo/query.
1783          */
1784         else if (type == TOMOYO_QUERY)
1785                 atomic_inc(&tomoyo_query_observers);
1786         return 0;
1787 }
1788
1789 /**
1790  * tomoyo_poll_control - poll() for /sys/kernel/security/tomoyo/ interface.
1791  *
1792  * @file: Pointer to "struct file".
1793  * @wait: Pointer to "poll_table".
1794  *
1795  * Waits for read readiness.
1796  * /sys/kernel/security/tomoyo/query is handled by /usr/sbin/tomoyo-queryd .
1797  */
1798 int tomoyo_poll_control(struct file *file, poll_table *wait)
1799 {
1800         struct tomoyo_io_buffer *head = file->private_data;
1801         if (!head->poll)
1802                 return -ENOSYS;
1803         return head->poll(file, wait);
1804 }
1805
1806 /**
1807  * tomoyo_read_control - read() for /sys/kernel/security/tomoyo/ interface.
1808  *
1809  * @file:       Pointer to "struct file".
1810  * @buffer:     Poiner to buffer to write to.
1811  * @buffer_len: Size of @buffer.
1812  *
1813  * Returns bytes read on success, negative value otherwise.
1814  *
1815  * Caller holds tomoyo_read_lock().
1816  */
1817 int tomoyo_read_control(struct file *file, char __user *buffer,
1818                         const int buffer_len)
1819 {
1820         int len = 0;
1821         struct tomoyo_io_buffer *head = file->private_data;
1822         char *cp;
1823
1824         if (!head->read)
1825                 return -ENOSYS;
1826         if (mutex_lock_interruptible(&head->io_sem))
1827                 return -EINTR;
1828         /* Call the policy handler. */
1829         head->read(head);
1830         if (len < 0)
1831                 goto out;
1832         /* Write to buffer. */
1833         len = head->read_avail;
1834         if (len > buffer_len)
1835                 len = buffer_len;
1836         if (!len)
1837                 goto out;
1838         /* head->read_buf changes by some functions. */
1839         cp = head->read_buf;
1840         if (copy_to_user(buffer, cp, len)) {
1841                 len = -EFAULT;
1842                 goto out;
1843         }
1844         head->read_avail -= len;
1845         memmove(cp, cp + len, head->read_avail);
1846  out:
1847         mutex_unlock(&head->io_sem);
1848         return len;
1849 }
1850
1851 /**
1852  * tomoyo_write_control - write() for /sys/kernel/security/tomoyo/ interface.
1853  *
1854  * @file:       Pointer to "struct file".
1855  * @buffer:     Pointer to buffer to read from.
1856  * @buffer_len: Size of @buffer.
1857  *
1858  * Returns @buffer_len on success, negative value otherwise.
1859  *
1860  * Caller holds tomoyo_read_lock().
1861  */
1862 int tomoyo_write_control(struct file *file, const char __user *buffer,
1863                          const int buffer_len)
1864 {
1865         struct tomoyo_io_buffer *head = file->private_data;
1866         int error = buffer_len;
1867         int avail_len = buffer_len;
1868         char *cp0 = head->write_buf;
1869
1870         if (!head->write)
1871                 return -ENOSYS;
1872         if (!access_ok(VERIFY_READ, buffer, buffer_len))
1873                 return -EFAULT;
1874         /* Don't allow updating policies by non manager programs. */
1875         if (head->write != tomoyo_write_pid &&
1876             head->write != tomoyo_write_domain_policy &&
1877             !tomoyo_policy_manager())
1878                 return -EPERM;
1879         if (mutex_lock_interruptible(&head->io_sem))
1880                 return -EINTR;
1881         /* Read a line and dispatch it to the policy handler. */
1882         while (avail_len > 0) {
1883                 char c;
1884                 if (head->write_avail >= head->writebuf_size - 1) {
1885                         error = -ENOMEM;
1886                         break;
1887                 } else if (get_user(c, buffer)) {
1888                         error = -EFAULT;
1889                         break;
1890                 }
1891                 buffer++;
1892                 avail_len--;
1893                 cp0[head->write_avail++] = c;
1894                 if (c != '\n')
1895                         continue;
1896                 cp0[head->write_avail - 1] = '\0';
1897                 head->write_avail = 0;
1898                 tomoyo_normalize_line(cp0);
1899                 head->write(head);
1900         }
1901         mutex_unlock(&head->io_sem);
1902         return error;
1903 }
1904
1905 /**
1906  * tomoyo_close_control - close() for /sys/kernel/security/tomoyo/ interface.
1907  *
1908  * @file: Pointer to "struct file".
1909  *
1910  * Releases memory and returns 0.
1911  *
1912  * Caller looses tomoyo_read_lock().
1913  */
1914 int tomoyo_close_control(struct file *file)
1915 {
1916         struct tomoyo_io_buffer *head = file->private_data;
1917         const bool is_write = !!head->write_buf;
1918
1919         /*
1920          * If the file is /sys/kernel/security/tomoyo/query , decrement the
1921          * observer counter.
1922          */
1923         if (head->type == TOMOYO_QUERY)
1924                 atomic_dec(&tomoyo_query_observers);
1925         else
1926                 tomoyo_read_unlock(head->reader_idx);
1927         /* Release memory used for policy I/O. */
1928         kfree(head->read_buf);
1929         head->read_buf = NULL;
1930         kfree(head->write_buf);
1931         head->write_buf = NULL;
1932         kfree(head);
1933         head = NULL;
1934         file->private_data = NULL;
1935         if (is_write)
1936                 tomoyo_run_gc();
1937         return 0;
1938 }
1939
1940 /**
1941  * tomoyo_check_profile - Check all profiles currently assigned to domains are defined.
1942  */
1943 void tomoyo_check_profile(void)
1944 {
1945         struct tomoyo_domain_info *domain;
1946         const int idx = tomoyo_read_lock();
1947         tomoyo_policy_loaded = true;
1948         /* Check all profiles currently assigned to domains are defined. */
1949         list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
1950                 const u8 profile = domain->profile;
1951                 if (tomoyo_profile_ptr[profile])
1952                         continue;
1953                 panic("Profile %u (used by '%s') not defined.\n",
1954                       profile, domain->domainname->name);
1955         }
1956         tomoyo_read_unlock(idx);
1957         if (tomoyo_profile_version != 20090903)
1958                 panic("Profile version %u is not supported.\n",
1959                       tomoyo_profile_version);
1960         printk(KERN_INFO "TOMOYO: 2.3.0-pre   2010/06/03\n");
1961         printk(KERN_INFO "Mandatory Access Control activated.\n");
1962 }